There are many hydraulically actuated elevating mechanisms such as farm wagon dump boxes, hydraulically operated back hoes, mobile crane units, and the like, which require positive stabilizers for maximum stability during operation of the principal hydraulic apparatus. In the case of farm wagon dump boxes, it is important for the safe operation thereof to provide for a rigid stabilizing strut unit between the wagon bolster and the front turning axle of the wagon. A hydraulic cylinder system elevates the wagon box and dumps the same, and, in the past, mechanical stabilizers have been provided, such as are shown in Gerald W. Bishop U.S. Pat. No. 3,995,894 assigned to GilmoreTatge Manufacturing Co. of Clay Center, Kans. It is important with such wagon units that during the wagon elevating and dumping operation, the wagon frame or bolster assembly be rigidly supported on the steering axle of the wagon to provide the wagon frame with four-point stabilized support. This is particularly critical when the wagon unit is being operated on uneven ground where one of the steering wheels is at a different elevation from the other wheel and it is desired to maintain the wagon rigidly stabilized on both sides of the front axle.